Copper-based bimetallic metal-organic framework in-situ embedded of heterogeneous Cu nanoparticles for enhanced nonenzymatic glucose sensing

Copper-based metal-organic frameworks (MOFs) are recently emerging as encouraging electrocatalysts with high performance and stability for electrochemical detection of glucose. Herein, a simple one-step solvothermal in-situ derivative strategy is proposed to fabricate the novel heterogeneous electrocatalyst of Cu nanoparticles embedded bimetallic Cu@MCu-BDC-NH2 (M = Ni, Co and Zn) MOFs, which can enhance the conductivity via tailor the electronic structure and heterojunction interface. The optimal bimetallic Cu@CoCu-BDC-NH2 heterostructure exposes more active sites, the electronic interaction between metal-O enhanced the reactivity and electrical conductivity, and prominently boost the kinetics of glucose detection. The optimized Cu@CoCu-BDC-NH2 heterojunction structure as modified electrode nanomaterials exhibit the low detection limit (0.27 mu M), wide linear range (0.5 mu M-2 mM) and the high sensitivity (21157 mu A mM(-1) cm(-2)), which are successfully used in human serum and hold great stability and anti-interference. The density functional theory (DFT) calculation demonstrates that the adsorption energies of Cu@CoCu-BDC-NH2 heterostructure for glucose are -0.3 eV, suggesting good adsorption capacity for glucose. This work not only successfully establish Cu nanoparticles heterostructure interface with bimetallic MOFs for high-performance glucose sensors, but also emphasizes the importance of regulate the electronic microstructure of bimetallic MOFs for enhanced reaction kinetics.